Plum tree named ‘Suplumfiftyseven’

ABSTRACT

A new and distinct plum tree variety, Prunus salicina, cv. ‘Suplumfiftyseven’ is characterized by fruit that is large, with black skin and dark red flesh and ripens early in the season. The fruit of the new variety ‘Suplumfiftyseven’ also has firm flesh, a mildly sweet flavor and a stone that is adherent to the flesh.

Latin name of the genus and species claimed: Prunus salicina.

Variety denomination: ‘Suplumfiftyseven’.

BACKGROUND AND SUMMARY OF THE INVENTION

This application relates to the discovery and asexual propagation of a new and distinct variety of plum tree, Prunus salicina cv. ‘Suplumfiftyseven’. The new variety was first originated by hybridization and identified in July 2014 by Terry A. Bacon as breeder number ‘PL1680RB’.

The seed parent is ‘Suplumfortyseven’ (U.S. Plant Pat. No. 27,503), and the pollen parent is from bulk pollen of several late-ripening plum cultivars having black skin and red flesh. The parent varieties were first crossed in February 2011, with the date of first sowing being February 2012, and the date of first flowering being February 2014. The new plum variety ‘Suplumfiftyseven’ was first asexually propagated by Terry Bacon near Wasco, Kern County, Calif. in February 2015 by dormant grafting.

The new variety ‘Suplumfiftyseven’ is characterized by having fruit that is large, with black skin and dark red flesh and that ripens early in the season. The fruit of the new variety ‘Suplumfiftyseven’ also has firm flesh, a mildly sweet flavor and a stone that is adherent to the flesh.

The new variety ‘Suplumfiftyseven’ resembles its seed parent ‘Suplumfortyseven’ in that both have fruit with black skin and red flesh. However, the fruit of the new variety ‘Suplumfiftyseven’ begins ripening about 30 days earlier than the fruit of ‘Suplumfortyseven’. Further, the fruit of the new variety ‘Suplumfiftyseven’ has a smaller size of about 140 gm compared to about 160 gm for ‘Suplumfortyseven’. The flowering time of the new variety ‘Suplumfiftyseven’ starts about 22 days earlier than that of ‘Suplumfortyseven’.

The new variety ‘Suplumfiftyseven’ has black skin and red flesh like ‘Black Splendor’ (unpatented), but the fruit of the new variety ‘Suplumfiftyseven’ begins ripening about 7 days later than the fruit of ‘Black Splendor’. Further, the fruit of the new variety ‘Suplumfiftyseven’ has a larger size than the fruit of ‘Black splendor’, at about 140 gm compared to 130 gm for ‘Black Splendor’. The new variety has a brix of 16% compared to 14% for ‘Black Splendor’, and the brix:acid ratio is 31 for the new variety ‘Suplumfiftyseven’ compared to 16 for ‘Black Splendor’. The new variety ‘Suplumfiftyseven’ also has black skin like ‘Black Amber’ (unpatented) and ‘Owen-T’ (unpatented), but the flesh color of the new variety is dark red compared to amber for ‘Black Amber’ and yellow for ‘Owen-T’.

The new variety ‘Suplumfiftyseven’ has been shown to maintain its distinguishing characteristics through successive asexual propagations by, for example, cuttings and grafting.

BRIEF DESCRIPTION OF THE PHOTOGRAPH

The accompanying color photographic illustration, FIG. 1, shows typical specimens of the foliage and fruit of the new plum variety ‘Suplumfiftyseven’. The illustration shows the upper and lower surface of the leaves, a view of the fruit as a whole, the stone as a whole, and a sectional view of a fruit divided across its suture plane to show flesh color, pit cavity and the stone remaining in place. The photographic illustration was taken shortly after being picked and the colors are as nearly true as is reasonably possible in a color representation of this type. The photographs depict fruit and vegetative growth from a three year old tree.

DETAILED DESCRIPTION

Throughout this specification, color names beginning with a small letter signify that the name of that color as used in common speech is aptly descriptive. Color names beginning with a capital letter designate values based upon The R.H.S. Colour Chart published by The Royal Horticultural Society, London, England, 1986.

The descriptive matter which follows pertains to three-year-old ‘Suplumfiftyseven’ plants grown in the vicinity of Wasco, Kern County, Calif. during 2017 and is believed to apply to plants of the variety grown under similar conditions of soil and climate elsewhere.

TREE

-   General: (Measurements taken on three year old trees unless     otherwise noted).     -   -   Size.—Medium: reaches a height of approximately 3 meters             with normal pruning.         -   Habit.—Semi-upright.         -   Vigor.—Medium: top shoot growth of about 1 meter during the             growing season.         -   Productivity.—Very productive, about 25,000 lbs/acre.         -   Bearer.—On spurs and long shoots.         -   Fertility.—Self-incompatible; requires pollinator.         -   Hardiness.—Hardy in all fruit growing areas of California.             Winter chilling requirement is approximately 550 hours at or             below 7.2° C.         -   Disease resistance/susceptibility.—Under close observation             in Kern County, Calif., no particular plant/fruit disease             resistance/susceptibility has been observed.         -   Insect resistance/susceptibility.—Under close observation in             Kern County, Calif., no particular plant/fruit insect             resistance/susceptibility has been observed. -   Trunk: (Measurements at approximately 30 cm above soil line on     mature tree).     -   -   Diameter.—Approximately 13 cm.         -   Texture.—Medium shaggy, increasing with age of tree.         -   Trunk color.—About Dark Greyed-Orange 166A, becoming darker             with age. -   Branches: (Measurements at approximately 90 cm above soil line).     -   -   Size.—Diameter approximately 7 cm.         -   Texture.—Medium shaggy, increasing with age.         -   Color.—About Dark Grey 201B with highlights of about Medium             Grey-Brown 199B, becoming darker with age.         -   Lenticels.—Present.         -   Lenticels density.—Plentiful, about 50/cm².         -   Lenticels color.—About Medium Greyed-Green 197C.         -   Lenticels dimensions.—Length: approximately 1-3 mm. Width:             approximately 0.5 mm. -   One year old shoots: (Data taken in September at mid-point of     current season growth).     -   -   Size.—Average diameter approximately 5 mm.         -   Topside color.—About Medium Green 137B, becoming Medium             Greyed-Orange 165B by September.         -   Underside color.—About Medium Green 137B, becoming Medium             Greyed-Orange 165B by September.         -   Internode length.—Approximately 25 mm. Midway on shoot.         -   Lenticels color.—About Medium Greyed-Green 197C.         -   Lenticels size.—Very small, difficult to see, about 0.2 mm             diameter.         -   Spur length.—Medium, usually 8 mm.         -   Anthocyanin intensity on upper side of shoot.—Medium. -   Vegetative buds:     -   -   Position of vegetative bud in relation to shoot.—Slightly             held out.         -   Size.—Medium, approximately 1.5 mm wide×2.5 mm long.         -   Shape.—Conical.         -   Bud shape at apex.—Acute.         -   Color.—About Dark Greyed-Orange 166A. -   Flower buds:     -   -   Shape.—Ovoid.         -   Dimensions.—Approximately 1.1 mm wide×2 mm long.         -   Color.—About Medium Yellow-Orange 177B.         -   Distribution.—2-6 buds, generally on spurs and one year old             shoots.         -   Ratio of flowering buds to vegetative buds.—2-6 flower buds             to 1 vegetative bud.

FOLIAGE

-   Leaves: (Data taken in July on fully expanded leaves at mid-point of     the current season growth).     -   -   Average length.—Medium; approximately 8.5 cm without             petiole.         -   Average width.—Medium; approximately 4.6 cm.         -   Length/width ratio.—Moderately elongated; about 1.8:1.         -   Color.—Upper surface: About Dark Green 139A. Lower surface:             About Medium Green 136C.         -   Glossiness of upper side.—Medium.         -   Angle at apex (excluding tip).—Acute.         -   Shape of base.—Acuminate.         -   Vein color.—About Light Green 139D with highlights of Medium             Greyed-Orange 176C where exposed to sun.         -   Venation.—Pinnately net veined.         -   Surface texture.—Smooth on both upper and lower surfaces.         -   Shape in the cross section.—Concave.         -   Profile.—Up folded.         -   Leaf blade tip.—Curved downwardly.         -   Undulation of margin.—Slight.         -   Density of pubescence of lower side.—Absent or very sparse.         -   Incisions of margin.—Bi-crenate. -   Petiole:     -   -   Average length.—Medium; approximately 10 mm.         -   Average diameter.—Approximately 2 mm.         -   Color.—About Light Green 139D with highlights of Medium             Greyed-Orange 176C where exposed to sun. -   Stipules:     -   -   Number/leaf bud.—Usually one.         -   Typical length.—Approximately 8 mm.         -   Color.—About Dark Greyed-Orange 166A when dried.         -   Persistence.—Falls off. -   Leaf glands:     -   -   Average number and arrangement.—Mostly Eglandular. Rarely             one on petiole.         -   Form.—Globose.         -   Diameter.—Approximately 0.3 mm.         -   Color.—About Medium Greyed-Yellow 162A becoming Dark             Greyed-Orange 166A over time.         -   Positions of nectarines (glands).—Rarely present, but             predominately on the petiole where found.

FLOWERS

-   General:     -   -   Time of beginning of flowering.—Medium for the San Joaquin             Valley, Calif.         -   Flower blooming period.—First bloom: Approximately February             24 in Wasco, Calif. Full bloom: Approximately February 28 in             Wasco, Calif.         -   Location of first bloom.—Tips of one year old shoots.         -   Location of full bloom.—Central part of the tree canopy.         -   Duration of bloom.—Approximately 10 days.         -   Flower diameter.—Medium, approximately 1.8 cm.         -   Flower form.—Showy. -   Pedicels:     -   -   Length.—Long, approximately 12 mm.         -   Diameter.—Approximately 1.2 mm.         -   Color.—About Light Green 138C.         -   Pubescence.—Absent. -   Petals:     -   -   Number.—5.         -   Arrangement.—Slightly overlapping.         -   Color.—About White 155A.         -   Length.—Medium, approximately 7.8 mm.         -   Width.—Approximately 7.9 mm.         -   Shape.—Circular.         -   Apex shape.—Rounded.         -   Base shape.—Narrows at point of attachment.         -   Surface texture.—Smooth.         -   Undulation of margins.—Medium.         -   Frequency of flowers with double petals.—None.         -   Claw.—Absent. -   Sepals:     -   -   Number.—5.         -   Length.—Approximately 4 mm.         -   Width.—Approximately 3 mm.         -   Shape.—Triangular.         -   Color.—About Light Green 138C.         -   Surface texture.—Smooth.         -   Margins.—Undulating.         -   Positioning.—Adpressed to petals.         -   Frequency of flowers with double sepals.—None. -   Stamens:     -   -   Number.—About 24-30; usually 28.         -   Average length.—Variable, ranging from 3 mm to 10 mm.         -   Filament color.—About White 155A.         -   Flower pollen color.—About Light Yellow-Orange 18A.         -   Position.—Perigynous. -   Pistil:     -   -   Average length.—Approximately 3-4 mm.         -   Ovary diameter.—Approximately 2.2 mm.         -   Pubescence.—Absent.         -   Stigma extension in comparison to anthers.—Usually below.         -   Style frequency of supplementary pistils.—Few. -   Receptacle:     -   -   Depth.—Medium, approximately 4 mm.         -   Pubescence of inner surface.—Absent.         -   Pubescence of outer surface.—Absent.

FRUIT

-   General: (Description taken at firm-mature near Wasco, Kern County,     Calif.). -   Ripening:     -   -   Time of beginning of fruit ripening.—Early season.         -   Date of first pick.—Approximately June 15.         -   Date of last pick.—Approximately June 23. -   Size:     -   -   Height.—Tall, approximately 62 mm.         -   Diameter in line with suture plane.—Approximately 65 mm.         -   Diameter perpendicular to suture plane.—Broad, approximately             65 mm.         -   Average weight.—Large, approximately 140 gm. -   Peduncle:     -   -   Length of stem.—Short; approximately 7 mm.         -   Diameter of stem.—Approximately 3 mm.         -   Color of stem.—About Light Green 139D. -   Shape:     -   -   Viewed from apex.—Circular.         -   Viewed in-line with suture.—Circular.         -   Viewed from side, perpendicular to suture.—Circular.         -   Symmetry.—Symmetric or slightly asymmetric.         -   Shape of base.—Truncated.         -   Shape of apex.—Truncated. -   Fruit stem cavity:     -   -   Depth of stalk cavity.—Shallow; Approximately 6 mm.         -   Width of stalk cavity.—Medium; Approximately 12 mm.         -   Depth of suture.—Absent or very shallow. -   Fruit skin:     -   -   Thickness.—Medium; typical of most varieties.         -   Flavor.—Mildly-tart.         -   Adherence to flesh.—Strong.         -   Surface texture.—Slightly rippled.         -   Pubescence.—None.         -   Bloom on skin.—Strong.         -   Ground color.—Not visible.         -   Overcolor.—About Dark Black 202A.         -   Relative area of overcolor.—Whole surface.         -   Pattern of overcolor.—Solid.         -   Reticulation.—Present.         -   Tendency to crack.—Rare.         -   Number of lenticels.—Few, small and difficult to see. About             10/cm².         -   Size of lenticels.—Very small, approximately 0.2 mm. -   Flesh at firm-mature harvest stage:     -   -   Ripens.—Evenly.         -   Texture.—Crisp-juicy.         -   Flavor.—Mildly sweet; about 31 Brix:Acid.         -   Color.—About Dark Red 53B.         -   Firmness.—Firm; typically 10 lb pressure at harvest.         -   Juice.—Medium; able to squeeze free juice easily.         -   Acidity.—Medium; 0.51% titratable acidity.         -   Sweetness.—High; about 16% Brix at harvest.         -   Adherence to stone.—Adherent.         -   Amount of fiber.—Low. -   Fruit use: Fresh market. -   Fruit shipping and keeping quality: Good. -   Stone:     -   -   Stone freeness.—Cling.         -   Stone size.—Size: Medium. Length: Approximately 23 mm.             Diameter in line with suture plan: Approximately 18 mm.             Diameter perpendicular to suture plane: Approximately 10 mm.         -   Color.—About Medium Greyed-Orange 170B when dried.         -   Position of maximum diameter.—Middle.         -   Shape from lateral view.—Medium elliptic.         -   Shape from ventral view.—Narrow elliptic.         -   Shape from basal view.—Narrow elliptic.         -   Base shape.—Nearly straight.         -   Apex shape.—Pointed.         -   Stone ridges.—Rounded throughout.         -   Stone outgrowing keel.—Partially developed.         -   Ventrical edge.—Thin with wing toward middle.         -   Dorsal edge.—Narrow, shallow grooves throughout.         -   Fibers.—Not visible.         -   Symmetry in lateral view.—Symmetrical or slightly             asymmetrical.         -   Texture of lateral surface.—Slightly rough.         -   Width of stalk-end.—Medium.         -   Tendency to split.—Rare. 

What is claimed is:
 1. A new and distinct variety of plum tree as herein described and illustrated. 